One-piece wooden body pencil



Oct. 5, 1948. c. c. HARRIS I ONE-PIECE WOOD EN BODY PENCIL Filed June 9, 1944 ww s I I! m 5 W. I v at "Z "am 0 2 I a. 5 1 I I .A I Z Z 2. "2 51 x Patented Oct. 1948 UNITED STATES PATENT FICE ONE-PIECE WOODEN BODY PENCIL Carl C. Harris, Orange, Mass.

Application June 9, 1944, Serial No. 539,543

' 3 Claims. 1

This invention relates to improvements in wooden pencils in which the body of the pencil is successively sharpened as the marking element is used and the object of the invention is broadly to provide a pencil which can be more economically manufactured with respect to the material of the body of the pencil, the expense of manufacture and which may also result in saving of material of the marking element.

The principal object of theinvention is to provide a pencil having a one-piece integral body thereby avoiding such usual expensive manufacture.

A further object of the invention is to provide a pencil having an integral one-piece body in which the lead or other marking element of the pencil terminates sufficiently short of the end that the portion which is thrown away contains no lead or other marking element, thereby saving a, material amount of the marking element which would be otherwise wasted.

These and other objects and features of the invention will more fully appear from the following description and the accompanying drawings and will be particularly pointed out in the claims.

An illustrative form of apparatus for making the pencil of my invention is shown in the drawings, in which,

Fig. 1 is a side elevation partly in longitudinal section of a machine for burning an axial bore in a pencil body;

Fig. 2 shows a longitudinal median sectional view of a pencil body embodying the invention;

Fig. 2a is a transverse sectional view on line 2-2 of Fig. 2;

Fig. 3 is a similar longitudinal sectional view of a fiat pencil body, embodying the invention;

Fig. 3a is a transverse sectional View on line 3-3 of Fig. 3.

Fig. 4 is a perspective view of a pencil embodyll'lg the invention, part of the pencil being shown in longitudinal section, and illustrating the slightly roughened scorched surface of the wall of the bore; and,

Fig. 5 is a perspective view illustrating the manner in which an integral slab for producing a plurality of pencil bodies may be simultaneously bored in the manner above described.

Fig, 1 shows conventionally a casing I containing a high frequently current generator (not shown) which may be of any usual type for producing an electric current having a frequency of, for example, 375,000 cycles per second at approximately l0,000 volts. This high frequency current is conducted by a suitable preferably 2 water-cooled tubular conduit 2 through an induction or work coil 3 and induces a magnetic field surrounding the current carrying conductor. lthe strength of the magnetic field varies inverse- 1y as the distance from the current carrying con ductor and rapidly becomes negligible in value as this distance becomes appreciable. The metal boring rod 4 is positioned in axial alinement with the work coil with its end 5 within or in such proximity to work coil that the end 5 is heated to a sufficient burning temperature to cause it rapidly to penetrate and progressively to burn a hole axially in the wooden pencil body 6 which is moved longitudinally through the induction coil in the direction of the axis of the boring rod 4. As illustrated in Fig. l of the drawings suitable means are provided for rotating the boring rod 4 during the penetration thereof into the integral wooden body. In the construction shown one end of the boring rod d is seated in a clutch 1 on the shaft of an electric motor 8 the armature of which is rotated at a suitable speed and the opposite free end of the boring rod is positioned in proximity to and in axial alinement with the induction coil 3.

Suitable means are provided for guiding the pencil body in axial alinement with the boring rod. As illustrated in Fig. l the bracket 9 is fixedly mounted on the casing i and is provided with a boss it! having therein an extended guideway ii and in which is slidably mounted a plunger I2 having at its lower end a clutch I3 adapted detachably to engage the upper end por-' tion of the pencil body 6. As illustrated herein the lower end of the clutch i3 is slotted and is provided with external screw threads l4 and a tapered lower end portion I5 which is engaged by a complementarily inclined inner wall of a nut IS provided with internal screw threads to engage the screw threads M of the plunger so that when the end of the pencil body is inserted therein the screwing upwardly of the nut l5 will clamp the pencil body firmly in axial alinement with the plunger. When the high frequency current is turned on the upper end portion only of the boring rod 5 will be heated to a burning temperature and the plunger i2 may then be forced downwardly in the axial direction of the boring rod 4 to the dotted line position shown in Fig. 1 thereby causing the heated end of the boring rod to burn a hole axially into the pencil body throughout its length or such predetermined portion of its length as may be desired.

Inasmuch as the rod, for thus boring a hole longitudinally of the pencil body to receive the marking element of pencils such as usual lead pencils, is of small cross sectional area relative to its length means desirably are provided for preventing vibration of the rod as it is being inserted into the pencil body. As illustrated in Fig. 1 a guide l1, which is slidably mounted upon and fits the boring rod, is provided with a laterally extending arm [8 having at its end a cylindrical head [9 which slidably fits a vertical tubular member 20, the lower end of which is welded to the base of a bracket 2| having a vertical flange 22 which is bolted or otherwise fixedly secured to the lower end portion of the casing for the high frequency generator. The tubular member 20 is provided with a longitudinal slot 23 through which the arm l8 of the guide extends and which forms a guideway therefor. A spiral spring 24, the lower end of which is seated upon the base member 2i and the upper end of which engages the head l9 of the guide, normally tends to force the guide upwardly to a position near the upper end of the boring rod 4 but at a suflicient distance therefrom to be below the heated end portion of the boring rod and out of the magnetic field of the induction coil.

As the pencil body is moved downwardly its lower end passes through the induction coil and engages the heated upper end portion of the boring rod which is steadied in axial alinement with the pencil body by the guide I1. When the pencil body is forced downwardly it engages the guide I! and forces it downwardly so that wobbling or vibration of the boring rod is prevented throughout the boring operation. When the pencil body is retracted from the boring rod the guide I! will follow the lower end of the pencil body until it reaches its uppermost position in proximity to the, heated end of the boring rod.

While the boring mechanism and the means for guiding the pencil body are illustrated in Fig. 1 in a vertical position, it may be readily understood that the parts may be arranged in a horizontal or other position so long as axial alinement between the boring rod and pencil body is maintained.

In thus boring a hole longitudinally of the pencil body the heated end of the boring rod progressively consumes the wood engaged by it and the products of combustion escape along the narrow channel alongside the boring rod. The heat from the boring rod scorches or slightly chars the wall of the bore thereby providing an effective anchorage for adhesive injected into the bore or applied to or contained in the marking element, thus causing an intimate union between the marking element and the pencil body.

After the pencil body is thus bored a marking element, such as graphite lead or other suitable composition, may be inserted into the bore or the open end of the bore may be placed in contact with a die for extruding plastic marking composition into the bore with sufiicient compactness to produce a satisfactory pencil. As the charred wall of the bore is finely granular carbon it will merge with the graphitic lead which itself contains finely granular carbon.

While the mechanism herein illustrated constitutes means for boring a hole of cylindrical form into the pencil body by reason of the rotation of the boring rod, it is obvious that the boring rod may be of square or other angular form and non-rotatable to form bores to fit leads of angular cross section.

Fig. conventionally illustrates mechanism for boring a plurality of holes in parallelism in a suitable slab of rectangular cross sectional area which may be divided longitudinally intermediate of the bores to provide a plurality of pencil bodies each ready to receive a marking element. As illustrated the apparatus comprises a base 25 having rigidly mounted in it a series of straight rods 26 of suitable cross sectional form and area with an induction coil 21' surrounding or in such suitable proximity to the free ends of the rods 26 that when a high frequency induction current is passed through the induction coil 2'! the end portions only of the rods will be simultaneously heated to a burning heat. A rectangular block or slab of wood 28 of suitable width and thickness is illustrated as being superposed over the rods and adapted to be forced downwardly in such manner as simultaneously to bore by burning holes of such length into the block or slab as may be desired to produce pencils of a predetermined length. Such holes may extend completely through the length of the block or slab or may terminate a desired distance short thereof for the purpose of economy in the use of the marking element.

After having been bored in the manner described the slab or block may besevered lengthwise into parallel sections as illustrated by the dotted lines 29 to provide a plurality of pencil bodies which may then be filled with a marking element and finished to the desired form.

Pencils made according to the instant invention are particularly adapted to be inserted between the pages of a book to form a marker or of a memorandum book for convenience in carrying the pencil and book the blank being made of any suitable thinness because. of the accuracy of the axial boring of the pencil body.

The present invention will permit a considerable saving or" wood by the use of thin metal slabs over that which would be required if the pencil bodies were made of usual cylindrical or hexagonal form and thereafter planed down to form a thin pencil body having oppositely relatively wide fi-at faces. Such saving is graphically illustrated in Fig. 3 which shows in dotted lines the cross sectional area of a cylindrical pencil and in cross section the area of the thin pencil body, the segments between the upper and lower faces of the thin pencil body and the dotted lines representing the wastage of Wood which would occur if usual pencils were thinned in the manner above described.

Pencils having one-piece integral bodies of the character above described can be readily distinguished from usual pencils by observation of the ends of the pencil because of the absence of any mark showing the union between the two halves of the body as in usual pencils, and also because there is no interruption in the lines of the grain of the wood as are clearly observable in lead pencils having bodies formed of complementary halves glued together.

It will be apparent that by reason of the present invention pencils having integral one-piece wooden bodies may be provided and that very considerable economy will result in the manufacture of the pencils by the'methods and means herein described both in respect to saving of labor. material of the wooden pencil body, and also a saving of graphite or other expensive marking element by its termination short of the stub of the pencil which is thrown away.

It will be understood that any suitable means either hand operated or mechanically operated may be employed to perform the process and to produce the article herein described within the meaning and scope of the following claims.

Having thus described the invention, what is claimed as new, and desired to be secured by Letters Patent, is:

1. A pencil comprising an integral straight wooden body of uniform cross sectional area having an axially burned bore of small diameter provided with a thinly charred wall and a graphitic lead filling said bore firmly united to said charred wall.

2. A pencil comprising an integral straight wooden body of uniform cross sectional area having an axially burned bore of small diameter provided with a thinly charred wall and a graphitic lead filling said bore firmly united to said charred wall, said lead-containing bore extending inwardly from one end of said body and terminating at such distance from the other end thereof as to provide beyond said bore a stub adapted to be conveniently grasped by the hand of the user and permit resharpening of the pencil until the lead is completely consumed.

3. A thin lead pencil comprising an integral straight wooden body of uniform cross sectional area having narrowly spaced fiat sides and having an axially burned bore of small diameter provided with a thinly charred wall and a graphitic lead filling said bore firmly united to said charred wall.

CARL C. HARRIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 15 Number Name Date 22,985 Smith Feb. 15, 1859 781,557 Von Schemnitzky Jan. 31, 1905 893,367 Promberger July 14, 1908 1,149,731 Coleman Aug. 10, 1915 20 2,044,263 Stoyan June 16, 1936 2,101,912 Meyer Dec. 14, 1937 2,374,706 Saslaw May 1, 1945 

